From Default Mode Network to the Basal Configuration: Sex Differences in the Resting-State Brain Connectivity as a Function of Age and Their Clinical Correlates.
Sean D Conrin, Liang Zhan, Zachery D Morrissey, Mengqi Xing, Angus Forbes, Pauline Maki, Mohammed R. Milad, Olusola Ajilore, Scott A Langenecker, Alex D Leow
Frontiers in Psychiatry 2018 DOI: 10.3389/fpsyt.2018.00365 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational study using existing connectome datasets (F1000 and Human Connectome Project) Peer reviewed |
|---|---|
| Population | Adults aged 22-35 from the 1,000 functional connectomes project (F1000) and the Human Connectome Project (HCP) |
| Topics | Default mode network |
| Keywords | Brain connectivity Community structure Human connectome project Modularity Resting-State FMRI Sex differences |
| Key findings | Sex differences in resting-state connectivity were not significant at ages 22-25 but reached significance at ages 26-30 (p = 0.003) and 31-35 (p < 0.001), with diverging areas including prefrontal cortex, temporal lobe, amygdala, hippocampus, inferior parietal lobule, posterior cingulate, and precuneus. The authors argue these findings support a basal configuration framework in which the resting-state connectome is dynamically modulated by both age and sex, and they report that self-reported inattention, hyperactivity, and anxiety scores differed between men and women and interacted divergently with age and basal configuration. |
Abstract
Connectomics is a framework that models brain structure and function interconnectivity as a network, rather than narrowly focusing on select regions-of-interest. MRI-derived connectomes can be structural, usually based on diffusion-weighted MR imaging, or functional, usually formed by examining fMRI blood-oxygen-level-dependent (BOLD) signal correlations. Recently, we developed a novel method for assessing the hierarchical modularity of functional brain networks-the probability associated community estimation (PACE). PACE uniquely permits a dual formulation, thus yielding equivalent connectome modular structure regardless of whether positive or negative edges are considered. This method was rigorously validated using the 1,000 functional connectomes project data set (F1000, RRID:SCR_005361) (1) and the Human Connectome Project (HCP, RRID:SCR_006942) (2, 3) and we reported novel sex differences in resting-state connectivity not previously reported. (4) This study further examines sex differences in regard to hierarchical modularity as a function of age and clinical correlates, with findings supporting a basal configuration framework as a more nuanced and dynamic way of conceptualizing the resting-state connectome that is modulated by both age and sex. Our results showed that differences in connectivity between men and women in the 22-25 age range were not significantly different. However, these same non-significant differences attained significance in both the 26-30 age group (p = 0.003) and the 31-35 age group (p < 0.001). At the most global level, areas of diverging sex difference include parts of the prefrontal cortex and the temporal lobe, amygdala, hippocampus, inferior parietal lobule, posterior cingulate, and precuneus. Further, we identified statistically different self-reported summary scores of inattention, hyperactivity, and anxiety problems between men and women. These self-reports additionally divergently interact with age and the basal configuration between sexes.
Comparable studies
Other observational and cohort studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| A default mode of brain function Normal adult human brain | 2001 | Observational study | |
| Resting-State Functional Connectivity Reflects Structural Connectivity in the Default Mode Network Healthy subjects | 2008 | Observational cohort | |
| Meditation experience is associated with increased cortical thickness Participants with extensive Insight meditation experience and matched controls | 2005 | Observational cohort | n = 20 |
| Meditation experience is associated with differences in default mode network activity and connectivity Experienced meditators and matched meditation-naive controls | 2011 | Observational cohort | |
| The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial correlation network analysis Healthy subjects | 2008 | Observational study |